Some other Bash tips

Expansion

As we saw in the last episode 1951 (and others in this sub-series) there are eight types of expansion applied to the command line in the following order:

• Brace expansion (we looked at this subject in episode 1884)
• Tilde expansion (seen in episode 1903)
• Parameter and variable expansion (this was covered in episode 1648)
• Command substitution (seen in episode 1903)
• Arithmetic expansion (seen in episode 1951)
• Process substitution
• Word splitting
• Pathname expansion

We will look at process substitution and word splitting in this episode but since there is a lot to cover in these subjects, we'll save pathname expansion for the next episode.

I have written out a moderately long set of notes about this subject and these are available here https://hackerpublicradio.org/eps/hpr2045/full_shownotes.html.

Links

• HPR episode 1648 "Bash parameter manipulation": https://hackerpublicradio.org/eps.php?id=1648
• HPR episode 1843 "Some Bash tips": https://hackerpublicradio.org/eps.php?id=1843
• HPR episode 1884 "Some more Bash tips": https://hackerpublicradio.org/eps.php?id=1884
• HPR episode 1903 "Some further Bash tips": https://hackerpublicradio.org/eps.php?id=1903
• HPR episode 1951 "Some additional Bash tips": https://hackerpublicradio.org/eps.php?id=1951
  
  
• "Introduction to sed" series on HPR:
  • Part 1: https://hackerpublicradio.org/eps.php?id=1976
  • Part 2: https://hackerpublicradio.org/eps.php?id=1986
  • Part 3: https://hackerpublicradio.org/eps.php?id=1997
  • Part 4: https://hackerpublicradio.org/eps.php?id=2011
    
    
• Wikipedia article on the "Named pipe": https://en.wikipedia.org/wiki/Named_pipe
• Wikipedia article on the "IFS" variable: https://en.wikipedia.org/wiki/Internal_field_separator
• Advanced Bash-Scripting Guide: Section 9.1 Bash Internal Variables (including IFS): https://www.tldp.org/LDP/abs/html/internalvariables.html

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